NEW YORK (AP) — The latest book project for “Cloud Atlas” novelist David Mitchell was released in England this summer to excellent reviews and strong sales, reaching the top 10 on Amazon.com.

“The Reason I Jump,” coming out in the U.S. next month, is a memoir about autism and a deeply personal book for Mitchell, the father of an autistic boy. But he is not the author. “The Reason I Jump” is a Japanese publication written by Naoki Higashida, a 21-year-old author and motivational speaker who was 13 when he completed the book.

Mitchell and his wife, K.A. Yoshida, were the translators.

“My wife had been hearing about the book and when she got a copy of it, in Japanese, she found it quite revelatory,” Mitchell said during a recent interview. “She started off interpreting the passages she felt were most useful in the book, but in the end she was reading through the whole thing.”

Higashida’s book, for which Mitchell also wrote an introduction, is a rarity in the publishing world. Translation is mostly the work of academics and professionals, with Gregory Rabassa, Edith Grossman and William Weaver among the most celebrated. Richard Wilbur, John Ashbery and countless other poets also translate books, some quite successfully. Seamus Heaney’s edition of “Beowulf” was a surprise best-seller in 2000 and Wilbur’s editions of Moliere’s plays are widely used in stage productions.

But among prose writers, the list is relatively tiny. In the 1950s, Saul Bellow translated Isaac Bashevis Singer’s short story “Gimpel the Fool” and helped introduce the Yiddish writer to English-language readers. Vladimir Nabokov translated Pushkin’s classic verse novel “Eugene Onegin.” Jonathan Franzen has a book out this fall, “The Kraus Project,” which features his translations of the late Austrian satirist and critic Karl Kraus. Lydia Davis is a prize-winning author of short stories whose many translations include an edition of Flaubert’s “Madame Bovary.”

“I think the main obstacle must purely be length,” said Adam Thirlwell, a British author whose books include “The Delighted States,” an informal history of novels, novelists and translations. “A translation is a very difficult object to create: For a novelist to translate someone else’s novel therefore requires a certain selflessness — a sacrifice of your own writing time to someone else.”

One way for a prose writer to find time is by spreading out the work. Franzen’s editor at Farrar, Straus & Giroux, Jonathan Galassi, notes that the author had been working on the Kraus book since the 1980s. During those years, Franzen completed four novels, including “The Corrections” and “Freedom,” and such nonfiction books as the memoir “The Discomfort Zone” and the essay collection “How To Be Alone.”

The new release is an unusual hybrid of translation and memoir. “The Kraus Project” features side by side German and English texts of Kraus’ writings with annotation by Franzen that reaches well beyond commentary. Franzen will often begin with an observation about Kraus and then segue to more personal and contemporary subjects, whether memories of sexual encounters in his early 20s, reflections on the influence of Thomas Pynchon or thoughts on technology, including a lament that people now depend on iPhones to check a fact they once knew from memory.

“The techno-boosters, of course, see nothing wrong here. They point out that human beings have always outsourced memory — to, bards, historians, spouses, books,” he writes. “But I’m enough of a child of the ’60s to see a difference between letting a spouse remember your nieces’ birthdays and handing over basic memory function to global corporate control.”

Even the book’s cover is a departure, reversing the usual billing for author and translator. The title may be “The Kraus Project,” but featured placement and the biggest letters belong to Franzen.

“To me, this is a Franzen book,” Galassi said. “It’s not just a translation. And we try to show that, typographically.”

Another prose writer-translator, Lynne Sharon Schwartz, said she has turned to translation when her own work wasn’t going well. The author of four novels and two story collections, Schwartz has also translated nonfiction works by the Italian writers Natalia Ginzburg and Liana Millu and said she enjoyed working on projects where the burden of invention was on someone else.

“For me, the first drafts of my own work are the most difficult; after that, the editing and revising are a pleasure. So in translation I can skip that hard part, and go directly to what I enjoy — the tinkering with words, phrases, and sentence,” she said.

“So I don’t have a problem balancing translating with writing. They are complementary: One feeds the other. In the case of Ginzburg I was so influenced by her style, which I had to replicate in English, that I found myself sounding like her in my writing, and had to watch out for that.”

Mitchell says that at first he and his wife simply wanted to translate the book for their son’s caretakers. But “one thing led to another” and he realized that his publisher, Random House, was interested in any book with his name on it, even as a translator.

Mitchell and Yoshida took turns editing drafts of the book, with Mitchell drawing upon his “high intermediate” level of Japanese, along with a dictionary and, Franzen be warned, the occasional search on his iPhone. The pace was “relaxed,” said Mitchell, who all along was working on a novel of his own. A job that a full-time translator might have finished in weeks lasted about 18 months.

“The translation did distract me and take hours away from my novel, but in the long run it will pay dividends,” he said. “It stimulates a part of your brain that you don’t normally use. I think it will feed into my own writing in some ways I haven’t realized yet and in other ways that I’m already aware of.”